bluetooth: Switch BluetoothGattCharacteristic.value to DataView

BUG=579148

Review URL: https://codereview.chromium.org/1603893002

Cr-Commit-Position: refs/heads/master@{#370664}

third_party/WebKit/LayoutTests/bluetooth/characteristicvaluechanged.html

@@ -18,10 +18,10 @@ promise_test(() => {
                                               'readValue',
                                               'characteristicvaluechanged');
     }).then(results => {
-      let read_value = new Uint8Array(results[0]);
-      let event_value = new Uint8Array(results[1]);
-      // TODO(ortuno): The ArrayBuffer used to resolve the promise
-      // should be the same ArrayBuffer as the one saved in the
+      let read_value = results[0].buffer;
+      let event_value = results[1].buffer;
+      // TODO(ortuno): The DataView used to resolve the promise
+      // should be the same DataView as the one saved in the
       // characteristic.
       // http://crbug.com/543347
       // assert_equals(event.target.value, value);
@@ -41,11 +41,11 @@ promise_test(() => {
                                               'characteristicvaluechanged',
                                               3 /* attach 3 listeners */);
     }).then(results => {
-      let read_value = new Uint8Array(results[0]);
-      let event_values = results.slice(1).map(v => new Uint8Array(v));
+      let read_value = results[0].buffer;
+      let event_values = results.slice(1).map(v => v.buffer);
       for (let event_value of event_values) {
-        // TODO(ortuno): The ArrayBuffer used to resolve the promise
-        // should be the same ArrayBuffer as the one saved in the
+        // TODO(ortuno): The DataView used to resolve the promise
+        // should be the same DataView as the one saved in the
         // characteristic.
         // http://crbug.com/543347
         // assert_equals(event.target.value, value);

third_party/WebKit/Source/core/dom/DOMDataView.h

@@ -5,11 +5,12 @@
 #ifndef DOMDataView_h
 #define DOMDataView_h
 
+#include "core/CoreExport.h"
 #include "core/dom/DOMArrayBufferView.h"
 
 namespace blink {
 
-class DOMDataView final : public DOMArrayBufferView {
+class CORE_EXPORT DOMDataView final : public DOMArrayBufferView {
     DEFINE_WRAPPERTYPEINFO();
 public:
     typedef char ValueType;

third_party/WebKit/Source/modules/bluetooth/BluetoothGATTCharacteristic.cpp

@@ -7,6 +7,7 @@
 #include "bindings/core/v8/CallbackPromiseAdapter.h"
 #include "bindings/core/v8/ScriptPromise.h"
 #include "bindings/core/v8/ScriptPromiseResolver.h"
+#include "core/dom/DOMDataView.h"
 #include "core/dom/DOMException.h"
 #include "core/dom/ExceptionCode.h"
 #include "core/events/Event.h"
@@ -19,12 +20,13 @@ namespace blink {
 
 namespace {
 
-PassRefPtr<DOMArrayBuffer> ConvertWebVectorToArrayBuffer(
+PassRefPtr<DOMDataView> ConvertWebVectorToDataView(
     const WebVector<uint8_t>& webVector)
 {
     static_assert(sizeof(*webVector.data()) == 1, "uint8_t should be a single byte");
     RefPtr<DOMArrayBuffer> domBuffer = DOMArrayBuffer::create(webVector.data(), webVector.size());
-    return domBuffer;
+    RefPtr<DOMDataView> domDataView = DOMDataView::create(domBuffer, 0, webVector.size());
+    return domDataView;
 }
 
 } // anonymous namespace
@@ -51,16 +53,16 @@ BluetoothGATTCharacteristic* BluetoothGATTCharacteristic::take(ScriptPromiseReso
 }
 
 void BluetoothGATTCharacteristic::setValue(
-    const PassRefPtr<DOMArrayBuffer>& domBuffer)
+    const PassRefPtr<DOMDataView>& domDataView)
 {
-    m_value = domBuffer;
+    m_value = domDataView;
 }
 
 void BluetoothGATTCharacteristic::dispatchCharacteristicValueChanged(
     const WebVector<uint8_t>& value)
 {
-    RefPtr<DOMArrayBuffer> domBuffer = ConvertWebVectorToArrayBuffer(value);
-    this->setValue(domBuffer);
+    RefPtr<DOMDataView> domDataView = ConvertWebVectorToDataView(value);
+    this->setValue(domDataView);
     dispatchEvent(Event::create(EventTypeNames::characteristicvaluechanged));
 }
 
@@ -113,11 +115,11 @@ public:
         if (!m_resolver->executionContext() || m_resolver->executionContext()->activeDOMObjectsAreStopped())
             return;
 
-        RefPtr<DOMArrayBuffer> domBuffer = ConvertWebVectorToArrayBuffer(value);
+        RefPtr<DOMDataView> domDataView = ConvertWebVectorToDataView(value);
         if (m_webCharacteristic) {
-            m_webCharacteristic->setValue(domBuffer);
+            m_webCharacteristic->setValue(domDataView);
         }
-        m_resolver->resolve(domBuffer);
+        m_resolver->resolve(domDataView);
     }
 
     void onError(const WebBluetoothError& e) override

third_party/WebKit/Source/modules/bluetooth/BluetoothGATTCharacteristic.h

@@ -8,6 +8,7 @@
 #include "bindings/core/v8/ScriptWrappable.h"
 #include "core/dom/ActiveDOMObject.h"
 #include "core/dom/DOMArrayPiece.h"
+#include "core/dom/DOMDataView.h"
 #include "modules/EventTargetModules.h"
 #include "platform/heap/Handle.h"
 #include "public/platform/modules/bluetooth/WebBluetoothGATTCharacteristic.h"
@@ -48,7 +49,7 @@ public:
     static BluetoothGATTCharacteristic* take(ScriptPromiseResolver*, PassOwnPtr<WebBluetoothGATTCharacteristicInit>);
 
     // Save value.
-    void setValue(const PassRefPtr<DOMArrayBuffer>&);
+    void setValue(const PassRefPtr<DOMDataView>&);
 
     // WebBluetoothGATTCharacteristic interface:
     void dispatchCharacteristicValueChanged(const WebVector<uint8_t>&) override;
@@ -75,7 +76,7 @@ public:
     String uuid() { return m_webCharacteristic->uuid; }
 
     BluetoothCharacteristicProperties* properties() { return m_properties; }
-    PassRefPtr<DOMArrayBuffer> value() const { return m_value; }
+    PassRefPtr<DOMDataView> value() const { return m_value; }
     ScriptPromise readValue(ScriptState*);
     ScriptPromise writeValue(ScriptState*, const DOMArrayPiece&);
     ScriptPromise startNotifications(ScriptState*);
@@ -91,7 +92,7 @@ private:
     OwnPtr<WebBluetoothGATTCharacteristicInit> m_webCharacteristic;
     bool m_stopped;
     Member<BluetoothCharacteristicProperties> m_properties;
-    RefPtr<DOMArrayBuffer> m_value;
+    RefPtr<DOMDataView> m_value;
 };
 
 } // namespace blink

third_party/WebKit/Source/modules/bluetooth/BluetoothGATTCharacteristic.idl

@@ -14,12 +14,12 @@
     // TODO(ortuno): Add test to make sure service matches the service
     // used to call getCharacteristic.
     // readonly    attribute BluetoothGATTService     service;
-    readonly    attribute UUID                   uuid;
+    readonly    attribute UUID                  uuid;
     readonly    attribute BluetoothCharacteristicProperties properties;
-    readonly    attribute ArrayBuffer?             value;
+    readonly    attribute DataView?             value;
     // Promise<BluetoothGATTDescriptor>           getDescriptor(BluetoothDescriptorUUID descriptor);
     // Promise<sequence<BluetoothGATTDescriptor>> getDescriptors(optional BluetoothDescriptorUUID descriptor);
-    [CallWith=ScriptState] Promise<ArrayBuffer> readValue();
+    [CallWith=ScriptState] Promise<DataView>    readValue();
     [CallWith=ScriptState] Promise<void>        writeValue(BufferSource value);
     [CallWith=ScriptState] Promise<void>        startNotifications();
     [CallWith=ScriptState] Promise<void>        stopNotifications();